/Engine/Source/Editor/KismetCompiler/Public/KismetCompiler.h
Prunes any nodes that weren't visited from the graph, printing out a warning
virtual void PruneIsolatedNodes ( const [TArray](API\Runtime\Core\Containers\TArray)< [UEdGraphNode](API\Runtime\Engine\EdGraph\UEdGraphNode) * > & RootSet, [TArray](API\Runtime\Core\Containers\TArray)< [UEdGraphNode](API\Runtime\Engine\EdGraph\UEdGraphNode) * > & GraphNodes )